Fix function comments based on best practices from Effective Go

[BlakeMScurr]

Every exported function in a program should have a doc comment. The first sentence should be a summary that starts with the name being declared. From effective go.

I generated this with CodeLingo and I'm keen to get some feedback, but this is automated so feel free to close it and just say "opt out" to opt out of future CodeLingo outreach PRs.

[BlakeMScurr]

Looks like most of these changes are good like this, this, and this. It couldn't figure out how to add the function name smoothly here, so it just applied some formatting, I hope that's alright.

Let me know if you find this useful :smile:

Note: I've only updated functions that I know CodeLingo can rewrite nicely, but you can install it from the GitHub marketplace to review your PRs automatically and find all issues.